The news: The Interactive Advertising Bureau (IAB) forecasts US ad spend will rise 9.5% YoY in 2026, even as marketers navigate shifting consumer behavior and rising acquisition costs. 

Growth this year is expected to be driven by digital channels and the transition from AI pilots to agent-led completion.

The study, which draws on more than 200 US brand and agency buyers, indicates a market recalibrating around performance, retention, and automation rather than reach alone.

Five of the six top marketer priorities in 2026 are AI-driven:

• Gen AI in media planning
• Content optimization for AI engines
• Agentic ad buying and campaign execution
• Large language models (LLMs)
• AI as a full funnel solution

Why it’s worth watching: AI now sits at the center of planning, activation, and measurement. Seventy-three percent of marketers are optimizing content for AI-generated answers, per IAB, reshaping how creative is structured and discovered.

The shift is less about novelty and more about scale. Agentic systems are increasingly trusted to pace budgets, optimize creative, and adjust audiences in real time, per Fluency. 

At the same time, learning curves remain steep. Adapting to changing consumer behavior is now the top media investment challenge for ad buyers, per IAB, edging past 2024’s concerns about macroeconomic uncertainty. 

Implications for advertisers: Marketing’s shift from AI chatbots that assist teams to agentic systems that act on their behalf will continue to influence how budgets are modeled, how media plans are constructed, and how spend is allocated. 

Advertisers should plan for a world where agents shape budgets continuously, not annually, and where performance depends on how well data, creative, and measurement systems feed those agents. 

Auditing first-party data readiness, pressure-testing measurement across platforms, and designing creative for AI interpretation will better position campaigns for new business realities. 

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